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September 14th, 2017, 11:44 PM   #1
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Need help with a math problem.

In math class this problem plz explain how to solve and what work you did.

X=-9 x^2+3


X^2 is my way of saying x is squared.
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September 14th, 2017, 11:58 PM   #2
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Is the problem

$x = -\ 9 + x^2 + 3$ or $x = -\ 9x^2 + 3$?

There are FOUR methods to solve quadratic equations. Which ones have you been taught so far?

It is hard to help when you tell us nothing about what you have tried or even thought about.
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September 15th, 2017, 05:34 AM   #3
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The simplest thing to do is to use the "quadratic formula". Given a general quadratic equation, $\displaystyle ax^2+ bx+ c= 0$, you can apply "completing the square" to it to get $\displaystyle x= \frac{-b\pm\sqrt{b^2- 4ac}}{2a}$. Here 9x^2+ x= 3 is the same as 9x^2+ x- 3= 0 so a= 9, b= 1, and c= -3. So $\displaystyle x= \frac{-1\pm\sqrt{(-1)^2- 4(9)(-3)}}{2(9)}= \frac{-1\pm\sqrt{109}}{18}$.
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September 15th, 2017, 06:06 AM   #4
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Quote:
Originally Posted by JeffM1 View Post
Is the problem
$x = -\ 9 + x^2 + 3$ or $x = -\ 9x^2 + 3$?
Probably x = - 9 + x^2 + 3 : has simple integer solution...
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